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The 5 essential components of a data strategy

Despite heavy, long-term investments in data management, data problems at many organizations continue to grow. One reason is that data has traditionally been perceived as just one aspect of a technology project; it has not been treated as a corporate asset. Consequently, the belief was that traditional application and database planning efforts were sufficient to address ongoing data issues.

5/20/2020 5:58:25 AM +00:00

Xây dựng hệ thống tính toán song song cho bài toán tính FFT hữu hạn

Xử lý song song được xem là một giải pháp hiệu quả nhằm nâng cao hiệu năng tính toán của hệ thống, đặc biệt trong các bài toán yêu cầu về tốc độ xử lý nhanh trong khi khối lượng dữ liệu cần xử lý là rất lớn. Với một hệ thống xử lý song song, ngoài các giải thuật song song đòi hỏi phải có một cơ sở hạ tầng phần cứng song song đủ mạnh để thực thi các giải thuật này. Trong phạm vi của bài báo, nhóm tác giả đề xuất và xây dựng một hệ thống xử lý song song áp dụng cho bài toán tính FFT (Fast Fourier Transform) hữu hạn.

5/20/2020 5:49:29 AM +00:00

Phương pháp xây dựng cơ sở hạ tầng như một dịch vụ điện toán đám mây

Với mô hình triển khai công nghệ thông tin truyền thống của các đơn vị, doanh nghiệp thì cơ sở hạ tầng mạng, máy chủ, hệ thống, lưu trữ hoạt động một cách rời rạc, mỗi máy chủ được phân bổ cho các phòng ban khác nhau của đơn vị để chạy ứng dụng, chính vì vậy tài nguyên hệ thống không được sử dụng tối ưu, gây lãng phí, khó khăn trong quản lý và nâng cấp, mở rộng hệ thống. Vậy bài toán đặt ra là cần phải xây dựng mô hình tập trung tài nguyên máy chủ để chia sẻ cho nhiều ứng dụng cũng được sử dụng, thay vì phải đầu tư nhiều máy chủ vật lý cho các ứng dụng khác nhau, nay chỉ cần một số lượng máy chủ rất ít ví dụ một hoặc hai máy chủ vẫn có thể chạy được rất nhiều ứng dụng mà không cần đến máy chủ dự phòng. Phương pháp giải quyết bài toán trên là xây dựng mô hình đám mây IaaS (cơ sở hạ tầng như một dịch vụ).

5/20/2020 5:49:23 AM +00:00

A hybrid metaheuristic for the time-dependent vehicle routing problem with hard time windows

This article paper presents a hybrid metaheuristic algorithm to solve the time-dependent vehicle routing problem with hard time windows. Time-dependent travel times are influenced by different congestion levels experienced throughout the day. Vehicle scheduling without consideration of congestion might lead to underestimation of travel times and consequently missed deliveries.

5/20/2020 2:55:30 AM +00:00

A generalized multi-depot vehicle routing problem with replenishment based on LocalSolver

In this paper, we consider the multi depot heterogeneous vehicle routing problem with time windows in which vehicles may be replenished along their trips. Using the modeling technique in a new-generation solver, we construct a novel formulation considering a rich series of constraint conditions and objective functions.

5/20/2020 2:52:29 AM +00:00

Academic e-mail overload and the burden of “Academic Spam”

This article presents an editorial perspective on the challenges associated with e-mail management for academic physicians. We include 2-week analysis of our own e-mails as illustrations of the e-mail volume and content. We discuss the contributors to high e-mail volumes, focusing especially on unsolicited e-mails from medical/scientific conferences and open-access journals (sometimes termed “academic spam emails”), as these e-mails comprise a significant volume and are targeted to physicians and scientists. Our 2-person sample is consistent with studies showing that journals that use mass e-mail advertising have low rates of inclusion in recognized journal databases/resources. Strategies for managing e-mail are discussed and include unsubscribing, blocking senders or domains, filtering e-mails, managing one’s inbox, limiting e-mail access, and e-mail etiquette. Academic institutions should focus on decreasing the volume of unsolicited e-mails, fostering tools to manage e-mail overload, and educating physicians including trainees about e-mail practices, predatory journals, and scholarly database/resources.

5/20/2020 2:42:45 AM +00:00

Lecture Principles of distributed database systems - Chapter 18: Current issues

Lecture Principles of distributed database systems - Chapter 18: Current issues. In this chapter students will be able to: Data stream management, cloud data management, inputs & outputs, data stream management system (DSMS), DSMSs – novel problems, abstract system architecture, stream data models,...

5/19/2020 9:36:36 PM +00:00

Lecture Principles of distributed database systems - Chapter 17: Web data management

Lecture Principles of distributed database systems - Chapter 17: Web data management. In this chapter students will be able to: Web data management, web models, web search and querying, distributed XML processing, properties of web data, web graph, web data modeling, search engine architecture,...

5/19/2020 9:36:30 PM +00:00

Lecture Principles of distributed database systems - Chapter 16: Peer-to-peer data management

In this chapter students will be able to: Peer-to-peer data management, why high-level P2P data sharing? problem definition, peer reference architecture, potential benefits of P2P systems, P2P vs traditional distributed DBMS,...

5/19/2020 9:36:23 PM +00:00

Lecture Principles of distributed database systems - Chapter 15: Distributed object DBMS

Lecture Principles of distributed database systems - Chapter 15: Distributed object DBMS. In this chapter students will be able to: Distributed object DBMS, object models, object distribution, fundamental concepts, object distribution, fragmentation alternatives, horizontal fragmentation,...

5/19/2020 9:36:17 PM +00:00

Lecture Principles of distributed database systems - Chapter 14: Parallel database systems

Lecture Principles of distributed database systems - Chapter 14: Parallel database systems. In this chapter students will be able to: Parallel database systems, data placement and query processing, load balancing, database clusters, the database problem, multiprocessor objectives,...

5/19/2020 9:36:11 PM +00:00

Lecture Principles of distributed database systems - Chapter 13: Data replication

Lecture Principles of distributed database systems - Chapter 13: Data replication. In this chapter students will be able to: Data replication, consistency criteria, replication protocols, replication and failure management, execution model, replication issues, transactional consistency, update management strategies,...

5/19/2020 9:36:05 PM +00:00

Lecture Principles of distributed database systems - Chapter 12: Distributed reliability

In this chapter students will be able to: Fundamental definitions, faults to failures, types of faults, fault classification, fault tolerance measures, fault-tolerance measures, fault-tolerance measures, types of failures, local recovery management – architecture,...

5/19/2020 9:35:59 PM +00:00

Lecture Principles of distributed database systems - Chapter 11: Distributed concurrency control

Lecture Principles of distributed database systems - Chapter 11: Distributed concurrency control. In this chapter students will be able to: Concurrency control, execution history (or schedule), formalization of history, complete schedule, schedule definition, serial history, serializable history, serializability in distributed DBMS,...

5/19/2020 9:35:52 PM +00:00

Lecture Principles of distributed database systems - Chapter 10: Transaction concepts and models

In this chapter students will be able to: Transaction, transaction example – a simple SQL query, example transaction – SQL Version, termination of transactions, characterization, formalization, consistency degrees (cont’d), SQL-92 isolation levels,...

5/19/2020 9:35:46 PM +00:00

Lecture Principles of distributed database systems - Chapter 9: Multidatabase query processing

Lecture Principles of distributed database systems - Chapter 9: Multidatabase query processing. In this chapter students will be able to: query rewriting, optimization issues, mediator/wrapper architecture, advantages of M/W architecture, issues in MDB query processing, component DBMS autonomy,...

5/19/2020 9:35:40 PM +00:00

Lecture Principles of distributed database systems - Chapter 8: Distributed query optimization

Lecture Principles of distributed database systems - Chapter 8: Distributed query optimization. In this chapter students will be able to: Global query optimization, cost-based optimization, query optimization process, search space, search strategy, cost functions, total cost, total cost factors, response time, optimization statistics,...

5/19/2020 9:35:33 PM +00:00

Lecture Principles of distributed database systems - Chapter 7: Query decomposition and localization

Lecture Principles of distributed database systems - Chapter 7: Query decomposition and localization. In this chapter students will be able to: Query decomposition, normalization, restructuring – transformation rules, equivalent query, provides parallellism, eliminates unnecessary work, reduction for PHF, reduction for hybrid fragmentation.

5/19/2020 9:35:25 PM +00:00

Lecture Principles of distributed database systems - Chapter 6: Distributed query processing

Lecture Principles of distributed database systems - Chapter 6: Distributed query processing. In this chapter students will be able to: Overview, query decomposition and localization, distributed query optimization.

5/19/2020 9:35:19 PM +00:00

Lecture Principles of distributed database systems - Chapter 5: Semantic data control

Lecture Principles of distributed database systems - Chapter 5: Semantic data control. In this chapter students will be able to: view management, data security, semantic integrity control.

5/19/2020 9:35:13 PM +00:00

Lecture Principles of distributed database systems - Chapter 4: Database integration

Lecture Principles of distributed database systems - Chapter 4: Database integration. In this chapter students will be able to: Schema matching, schema mapping, problem definition, integration alternatives, data warehouse approach, GCS/LCS relationship,...

5/19/2020 9:35:07 PM +00:00

Lecture Principles of distributed database systems - Chapter 3: Distributed database design

Lecture Principles of distributed database systems - Chapter 3: Distributed database design. In this chapter students will be able to: Design problem, dimensions of the problem, distribution design, top-down design, distribution design issues, fragmentation alternatives – horizontal, degree of fragmentation,...

5/19/2020 9:35:00 PM +00:00

Lecture Principles of distributed database systems - Chapter 2: Background

Lecture Principles of distributed database systems - Chapter 2: Background. In this chapter students will be able to: relational model, relational database systems, computer networks, relation schemes and instances, relation schemes, repetition anomaly,...

5/19/2020 9:34:50 PM +00:00

Lecture Principles of distributed database systems - Chapter 1: Introduction

Lecture Principles of distributed database systems - Chapter 1: Introduction. In this chapter students will be able to: What is a distributed DBMS, distributed DBMS Architecture.

5/19/2020 9:34:44 PM +00:00

IT-Tree và thuật toán Apriori

Khám phá itemsets là công việc quan trọng trong khai thác dữ liệu. Nhờ đó mà ta có thể khai thác luật kết hợp từ các itemsets đó. Tuy nhiên, không gian tìm kiếm trong giai đoạn tìm các itemsets cần thiết thì rất lớn theo từng bước, độ dài k của các item.

5/19/2020 6:31:53 PM +00:00

Bài giảng Chương 4: Các thuật toán tìm kiếm

Nội dung bài giảng trình bày khái niệm tìm kiếm; bài toán tìm kiếm; các thuật toán tìm kiếm; tìm kiếm trên dãy chưa sắp; tìm kiếm tuần tự; tìm kiếm tuần tự cải tiến; tìm kiếm tuần tự trên dãy đã sắp... Để nắm chắc kiến thức mời các bạn cùng tham khảo bài giảng Chương 4: Các thuật toán tìm kiếm.

5/5/2020 12:28:16 AM +00:00

Lecture Database Systems - Lecture 32

After completing this chapter, students will be able to: The object-relational data model, which extends the relational data model to support complex data types, type inheritance, and object identity. The chapter also describes database access from object-oriented programming languages.

5/4/2020 5:22:09 PM +00:00

Lecture Database Systems - Lecture 31

After completing this chapter, students will be able to: Advanced issues in application development, including performance tuning, performance benchmarks, database-application testing, and standardization.

5/4/2020 5:22:03 PM +00:00

Lecture Database Systems - Lecture 30

After completing this chapter, students will be able to: Transaction-processing monitors, transactional workflows, electronic commerce, high-performance transaction systems, real-time transaction systems, and long-duration transactions.

5/4/2020 5:21:57 PM +00:00

Lecture Database Systems - Lecture 29

After completing this chapter, students will be able to: Basic concepts, tree-structure diagrams, data-retrieval facility, update facility, virtual records, mapping of hierarchies to files, the IMS database system.

5/4/2020 5:21:51 PM +00:00